We investigate the effect of ion irradiation on MgB_(2) thin films with small grains of approximately 122 nm and 140 nm.The flux pinning by grain boundaries is insignificant in the pristine MgB_(2) films due to good i...We investigate the effect of ion irradiation on MgB_(2) thin films with small grains of approximately 122 nm and 140 nm.The flux pinning by grain boundaries is insignificant in the pristine MgB_(2) films due to good inter-grain connectivity,but is significantly improved after 120-keV Mn-ion irradiation.The scaling behavior of the flux pinning force density for the ion-irradiated MgB_(2) thin films with nanoscale grains demonstrates the predominance of pinning by grain boundaries,in contrast to the single-crystalline MgB_(2) films where normal point pinning was dominant after low-energy ion irradiation.These results suggest that irradiation-induced defects can accumulate near the grain boundaries in metallic MgB_(2) superconductors.展开更多
Hepatitis B surface antigen (HBsAg) is produced and secreted through a complex mechanism that is still not fully understood. In clinical fields, HBsAg has long served as a qualitative diagnostic marker for hepatitis B...Hepatitis B surface antigen (HBsAg) is produced and secreted through a complex mechanism that is still not fully understood. In clinical fields, HBsAg has long served as a qualitative diagnostic marker for hepatitis B virus infection. Notably, advances have been made in the development of quantitative HBsAg assays, which have allowed viral replication monitoring, and there is an opportunity to make maximal use of quantitative HBsAg to elucidate its role in clinical fields. Yet, it needs to be underscored that a further understanding of HBsAg, not only from clinical point of view but also from a virologic point of view, would enable us to deepen our insights, so that we could more widely expand and apply its utility. It is also important to be familiar with HBsAg variants and their clinical consequences in terms of immune escape mutants, issues resulting from overlap with corresponding mutation in the P gene, and detection problems for the HBsAg variants. In this article, we review current concepts and issues on the quantification of HBsAg titers with respect to their biologic nature, method principles, and clinically relevant topics.展开更多
We report our experience with a synchronous case of gastrointestinal stromal tumor(GIST) and intraductal papillary neoplasm of the bile duct(IPNB) in anelderly woman with neurofibromatosis type 1(NF-1). A 72-year-old ...We report our experience with a synchronous case of gastrointestinal stromal tumor(GIST) and intraductal papillary neoplasm of the bile duct(IPNB) in anelderly woman with neurofibromatosis type 1(NF-1). A 72-year-old woman presented with a 2-mo history of right upper abdominal pain unrelated to diet and indigestion. Fourteen years earlier, she had been diagnosed with NF-1, which manifested as café au lait spots and multiple nodules on the skin. Computed tomography(CT) revealed a multilocular low-density mass with septation, and mural nodules in the right hepatic lobe, as well as a 1.7-cm-sized well-demarcated enhancing mass in the third portion of the duodenum. The patient subsequently underwent right hepatectomy and duodenal wedge resection. We present here the first report of a case involving a synchronous IPNB and GIST in a patient with NF-1. Our findings demonstrate the possibility of various tumors in NF-1 patients and the importance of diagnosis at an early展开更多
The development of memory devices with functions that simultaneously process and store data is required for efficient computation.To achieve this,artificial synaptic devices have been proposed because they can constru...The development of memory devices with functions that simultaneously process and store data is required for efficient computation.To achieve this,artificial synaptic devices have been proposed because they can construct hybrid networks with biological neurons and perform neuromorphic computation.However,irreversible aging of these electrical devices causes unavoidable performance degradation.Although several photonic approaches to controlling currents have been suggested,suppression of current levels and switching of analog conductance in a simple photonic manner remain challenging.Here,we demonstrated a nanograin network memory using reconfigurable percolation paths in a single Si nanowire with solid core/porous shell and pure solid core segments.The electrical and photonic control of current percolation paths enabled the analog and reversible adjustment of the persistent current level,exhibiting memory behavior and current suppression in this single nanowire device.In addition,the synaptic behaviors of memory and erasure were demonstrated through potentiation and habituation processes.Photonic habituation was achieved using laser illumination on the porous nanowire shell,with a linear decrease in the postsynaptic current.Furthermore,synaptic elimination was emulated using two adjacent devices interconnected on a single nanowire.Therefore,electrical and photonic reconfiguration of the conductive paths in Si nanograin networks will pave the way for next-generation nanodevice technologies.展开更多
基金the support of the accelerator group and operators of KOMAC (KAERI (C.K.,J.S.))Project supported by the National Research Foundation (NRF)of Korea through a grant funded by the Korean Ministry of Science and ICT (Grant No.2021R1A2C2010925 (T.P.,Y.H.,J.S.))+2 种基金the Basic Science Research Program through the NRF of Korea funded by the Ministry of Education (Grant Nos.NRF-2019R1F1A1055284 (J.M.L.,W.N.K.)and NRF2021R1I1A1A01043885 (S.G.J.,Y.H.))the National Natural Science Foundation of China (Grant Nos.12035019 (J.L.))the Chinese Scholarship Council (CSC)for fellowship support。
文摘We investigate the effect of ion irradiation on MgB_(2) thin films with small grains of approximately 122 nm and 140 nm.The flux pinning by grain boundaries is insignificant in the pristine MgB_(2) films due to good inter-grain connectivity,but is significantly improved after 120-keV Mn-ion irradiation.The scaling behavior of the flux pinning force density for the ion-irradiated MgB_(2) thin films with nanoscale grains demonstrates the predominance of pinning by grain boundaries,in contrast to the single-crystalline MgB_(2) films where normal point pinning was dominant after low-energy ion irradiation.These results suggest that irradiation-induced defects can accumulate near the grain boundaries in metallic MgB_(2) superconductors.
基金Supported by The Grant of the Bilateral International Collaborative R&D Program from the Ministry of Knowledge Economythe Good Health R&D Project from the Ministry for Health,Welfare and Family Affairs,South Korea (A050021)
文摘Hepatitis B surface antigen (HBsAg) is produced and secreted through a complex mechanism that is still not fully understood. In clinical fields, HBsAg has long served as a qualitative diagnostic marker for hepatitis B virus infection. Notably, advances have been made in the development of quantitative HBsAg assays, which have allowed viral replication monitoring, and there is an opportunity to make maximal use of quantitative HBsAg to elucidate its role in clinical fields. Yet, it needs to be underscored that a further understanding of HBsAg, not only from clinical point of view but also from a virologic point of view, would enable us to deepen our insights, so that we could more widely expand and apply its utility. It is also important to be familiar with HBsAg variants and their clinical consequences in terms of immune escape mutants, issues resulting from overlap with corresponding mutation in the P gene, and detection problems for the HBsAg variants. In this article, we review current concepts and issues on the quantification of HBsAg titers with respect to their biologic nature, method principles, and clinically relevant topics.
基金Supported by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute(KHIDI)funded by the Ministry of Health&Welfare,South Korea,No.HI14C3477by a grant from Korea University
文摘We report our experience with a synchronous case of gastrointestinal stromal tumor(GIST) and intraductal papillary neoplasm of the bile duct(IPNB) in anelderly woman with neurofibromatosis type 1(NF-1). A 72-year-old woman presented with a 2-mo history of right upper abdominal pain unrelated to diet and indigestion. Fourteen years earlier, she had been diagnosed with NF-1, which manifested as café au lait spots and multiple nodules on the skin. Computed tomography(CT) revealed a multilocular low-density mass with septation, and mural nodules in the right hepatic lobe, as well as a 1.7-cm-sized well-demarcated enhancing mass in the third portion of the duodenum. The patient subsequently underwent right hepatectomy and duodenal wedge resection. We present here the first report of a case involving a synchronous IPNB and GIST in a patient with NF-1. Our findings demonstrate the possibility of various tumors in NF-1 patients and the importance of diagnosis at an early
基金This work was supported by the National Research Foundation of Korea(NRF)funded by the Korean government(2021R1A2C3006781,2021R1A4A3029839,and 2022R1F1A1063837)H.-G.P.acknowledges a support from the Samsung Research Funding and Incubation Center of Samsung Electronics(SRFCMA2001-01).
文摘The development of memory devices with functions that simultaneously process and store data is required for efficient computation.To achieve this,artificial synaptic devices have been proposed because they can construct hybrid networks with biological neurons and perform neuromorphic computation.However,irreversible aging of these electrical devices causes unavoidable performance degradation.Although several photonic approaches to controlling currents have been suggested,suppression of current levels and switching of analog conductance in a simple photonic manner remain challenging.Here,we demonstrated a nanograin network memory using reconfigurable percolation paths in a single Si nanowire with solid core/porous shell and pure solid core segments.The electrical and photonic control of current percolation paths enabled the analog and reversible adjustment of the persistent current level,exhibiting memory behavior and current suppression in this single nanowire device.In addition,the synaptic behaviors of memory and erasure were demonstrated through potentiation and habituation processes.Photonic habituation was achieved using laser illumination on the porous nanowire shell,with a linear decrease in the postsynaptic current.Furthermore,synaptic elimination was emulated using two adjacent devices interconnected on a single nanowire.Therefore,electrical and photonic reconfiguration of the conductive paths in Si nanograin networks will pave the way for next-generation nanodevice technologies.